[evolution] Change how label actions are updated in EMailReader

[Milan Crha <mcrha src gnome org>]

commit 4a1883626196901586df738d34ad1f2a8b7c3443
Author: Milan Crha <mcrha redhat com>
Date:   Thu Feb 21 11:47:53 2019 +0100

    Change how label actions are updated in EMailReader
    
    This might be a bit more efficient implementation, where instead of
    accessing each selected message info as many times as many labels
    are defined (until one message with and one without the label is found),
    check each message info for the defined labels at once.

 src/mail/e-mail-reader.c | 131 ++++++++++++++++++++++++++++++++++-------------
 1 file changed, 94 insertions(+), 37 deletions(-)
---
diff --git a/src/mail/e-mail-reader.c b/src/mail/e-mail-reader.c
index 6992d2c306..c59cdab3e1 100644
--- a/src/mail/e-mail-reader.c
+++ b/src/mail/e-mail-reader.c
@@ -4107,19 +4107,100 @@ action_mail_label_cb (GtkToggleAction *action,
        g_ptr_array_unref (uids);
 }
 
+#define LABEL_UNKNOWN  0
+#define LABEL_EXISTS   (1 << 0)
+#define LABEL_NOTEXIST (1 << 1)
+
+static GHashTable *
+mail_reader_gather_labels_info (EMailReader *reader,
+                               EMailLabelListStore *label_store,
+                               GPtrArray *uids)
+{
+       GHashTable *labels_info;
+       CamelFolder *folder;
+       GtkTreeIter iter;
+       GtkTreeModel *model;
+       gboolean valid;
+       guint ii;
+
+       labels_info = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
+
+       model = GTK_TREE_MODEL (label_store);
+       folder = e_mail_reader_ref_folder (reader);
+
+       if (!folder)
+               return labels_info;
+
+       for (ii = 0; ii < uids->len; ii++) {
+               CamelMessageInfo *info;
+
+               info = camel_folder_get_message_info (folder, uids->pdata[ii]);
+               if (!info)
+                       continue;
+
+               for (valid = gtk_tree_model_get_iter_first (model, &iter);
+                    valid;
+                    valid = gtk_tree_model_iter_next (model, &iter)) {
+                       gchar *tag;
+                       guint value;
+
+                       tag = e_mail_label_list_store_get_tag (label_store, &iter);
+                       value = GPOINTER_TO_UINT (g_hash_table_lookup (labels_info, tag));
+                       if ((!(value & LABEL_EXISTS)) || (!(value & LABEL_NOTEXIST))) {
+                               gboolean exists = FALSE, notexist = FALSE;
+
+                               /* Check for new-style labels. */
+                               if (camel_message_info_get_user_flag (info, tag)) {
+                                       exists = TRUE;
+                               } else {
+                                       /* Check for old-style labels. */
+                                       const gchar *old_label = camel_message_info_get_user_tag (info, 
"label");
+                                       if (old_label) {
+                                               gchar *new_label;
+
+                                               /* Convert old-style labels ("<name>") to "$Label<name>". */
+                                               new_label = g_alloca (strlen (old_label) + 10);
+                                               g_stpcpy (g_stpcpy (new_label, "$Label"), old_label);
+
+                                               if (g_strcmp0 (new_label, tag) == 0)
+                                                       exists = TRUE;
+                                               else
+                                                       notexist = TRUE;
+                                       } else {
+                                               notexist = TRUE;
+                                       }
+                               }
+
+                               value = value |
+                                       (exists ? LABEL_EXISTS : LABEL_UNKNOWN) |
+                                       (notexist ? LABEL_NOTEXIST : LABEL_UNKNOWN);
+
+                               g_hash_table_insert (labels_info, tag, GUINT_TO_POINTER (value));
+
+                               /* the hash table took the 'tag' */
+                               tag = NULL;
+                       }
+
+                       g_free (tag);
+               }
+
+               g_clear_object (&info);
+       }
+
+       g_clear_object (&folder);
+
+       return labels_info;
+}
+
 static void
 mail_reader_update_label_action (GtkToggleAction *action,
-                                EMailReader *reader,
-                                GPtrArray *uids,
+                                GHashTable *labels_info, /* gchar * ~> guint */
                                 const gchar *label_tag)
 {
-       CamelFolder *folder;
        gboolean exists = FALSE;
        gboolean not_exists = FALSE;
        gboolean sensitive;
-       guint ii;
-
-       folder = e_mail_reader_ref_folder (reader);
+       guint value;
 
        /* Figure out the proper label action state for the selected
         * messages.  If all the selected messages have the given label,
@@ -4127,40 +4208,13 @@ mail_reader_update_label_action (GtkToggleAction *action,
         * DO NOT have the given label, make the toggle action inactive.
         * If some do and some don't, make the action insensitive. */
 
-       for (ii = 0; ii < uids->len && (!exists || !not_exists); ii++) {
-               const gchar *old_label;
-               gchar *new_label;
-
-               /* Check for new-style labels. */
-               if (camel_folder_get_message_user_flag (
-                       folder, uids->pdata[ii], label_tag)) {
-                       exists = TRUE;
-                       continue;
-               }
-
-               /* Check for old-style labels. */
-               old_label = camel_folder_get_message_user_tag (
-                       folder, uids->pdata[ii], "label");
-               if (old_label == NULL) {
-                       not_exists = TRUE;
-                       continue;
-               }
-
-               /* Convert old-style labels ("<name>") to "$Label<name>". */
-               new_label = g_alloca (strlen (old_label) + 10);
-               g_stpcpy (g_stpcpy (new_label, "$Label"), old_label);
-
-               if (strcmp (new_label, label_tag) == 0)
-                       exists = TRUE;
-               else
-                       not_exists = TRUE;
-       }
+       value = GPOINTER_TO_UINT (g_hash_table_lookup (labels_info, label_tag));
+       exists = (value & LABEL_EXISTS) != 0;
+       not_exists = (value & LABEL_NOTEXIST) != 0;
 
        sensitive = !(exists && not_exists);
        gtk_toggle_action_set_active (action, exists);
        gtk_action_set_sensitive (GTK_ACTION (action), sensitive);
-
-       g_clear_object (&folder);
 }
 
 static void
@@ -4174,6 +4228,7 @@ mail_reader_update_labels_menu (EMailReader *reader)
        GtkUIManager *ui_manager = NULL;
        GtkActionGroup *action_group;
        GtkTreeIter iter;
+       GHashTable *labels_info; /* gchar * ~> guint { LABEL_EXISTS | LABEL_NOTEXIST | LABEL_UNKNOWN } */
        GPtrArray *uids;
        const gchar *main_menu_path, *popup_menu_path;
        gboolean valid;
@@ -4215,6 +4270,7 @@ mail_reader_update_labels_menu (EMailReader *reader)
        gtk_ui_manager_ensure_update (ui_manager);
 
        uids = e_mail_reader_get_selected_uids (reader);
+       labels_info = mail_reader_gather_labels_info (reader, label_store, uids);
 
        valid = gtk_tree_model_get_iter_first (GTK_TREE_MODEL (label_store), &iter);
 
@@ -4239,7 +4295,7 @@ mail_reader_update_labels_menu (EMailReader *reader)
                        tag, (GDestroyNotify) g_free);
 
                /* Configure the action before we connect to signals. */
-               mail_reader_update_label_action (GTK_TOGGLE_ACTION (label_action), reader, uids, tag);
+               mail_reader_update_label_action (GTK_TOGGLE_ACTION (label_action), labels_info, tag);
 
                g_signal_connect (
                        label_action, "toggled",
@@ -4277,6 +4333,7 @@ mail_reader_update_labels_menu (EMailReader *reader)
                ii++;
        }
 
+       g_hash_table_destroy (labels_info);
        g_ptr_array_unref (uids);
 }